Wafer lossless composite ultrasonic cleaning system and working and regulating method thereof

Abstract

A wafer lossless composite ultrasonic cleaning system and a working and regulation method thereof are characterized in that a data processing analysis module (10) timely regulates the working state of a transduction module (4) by adopting a cavitation noise spectrum analysis method according to the ultrasonic cavitation effect in a water tank (7) and the working condition of a cleaning solution, which are acquired by a sound wave acquisition module (5) and a water pressure acquisition module (8) in real time; the data processing and analyzing module solves the problem that cavitation negative pressure is difficult to regulate and control in the wafer cleaning process according to the ultrasonic cavitation effect and the cleaning fluid working condition, collected by the sound wave collecting module and the water pressure collecting module in real time, in the water tank, and the defect that cleaning power is difficult to determine in a traditional ultrasonic cleaning device is overcome. Meanwhile, damage to the microstructure of the wafer caused by a traditional cleaning method is avoided, the purity of the surface of the wafer is ensured, and it is ensured that the performance and the structure of the transistor are not damaged. The steady cavitation intensity and the transient cavitation intensity of cavitation generated by ultrasonic cleaning of the transduction module are measured, so that the transduction module is in an optimal working state.

Description

Technical Field

[0001] The present invention belongs to the technical field of devices for processing wafers in the manufacturing or processing of semiconductor or electrical solid state devices or components of IPC classification H01L21 / 67, and in particular to a technology for ultrasonic cleaning of wafers which significantly improves the process and reduces processing damage. Background Art

[0002] Wafer is the basic material used to make silicon semiconductor circuits. Its original material is silicon. Wafer, also known as silicon slice or silicon chip, is made by dissolving high-purity polysilicon and adding silicon crystal seeds, and then slowly pulling it out to form a cylindrical single crystal silicon. After grinding, polishing, slicing and other processes, it finally forms a silicon wafer, that is, a wafer.

[0003] In the process of integrated circuit production, semiconductor wafers usually need to go through multiple process steps, such as thin film deposition, etching, polishing, etc., and these steps often produce various contaminants. If these contaminants are not removed in time, they will cause circuit short circuits, open circuits and other problems, seriously affecting the quality and yield of integrated circuits. The cleanliness of the wafer surface directly determines the performance and reliability of the final product.

[0004] The reduction in size of nanostructures and the stacking of different crystal layers result in a decrease in the mechanical strength of the material, making it more susceptible to external stress, while heterogeneous interfaces may cause local stress concentration; this requires wafer cleaning to meet higher requirements, not only to ensure the purity of the wafer surface, but also to ensure that the performance and structure of the transistor are not damaged.

[0005] Traditional wafer cleaning methods include chemical cleaning, ultrasonic cleaning, and water cleaning, which have some obvious limitations. Chemical cleaning or spray cleaning may leave chemical residues on the wafer surface, which may have a negative impact on the performance of semiconductor devices, especially on micro-nano wafers.

[0006] The application of ultrasonic technology can be roughly divided into two categories: one is the power application that requires relatively high or fairly high power ultrasonic waves and uses the characteristics of ultrasonic reflection, refraction, beam focusing and orientation to achieve the change of objects or objects, which is called power ultrasound; the other is the application of information collection and acquisition using ultrasonic waves, which is called detection ultrasound. Among them, power ultrasound technology is widely used. Wafer ultrasonic cleaning is a kind of power ultrasound technology. Ultrasonic cleaning does not require the use of a large amount of chemical reagents, which reduces environmental pollution and wastewater treatment costs. Ultrasonic cleaning is a non-contact cleaning method that will not cause obvious physical damage or scratches to the surface of the wafer.

[0007] At present, most of the generators used in the ultrasonic cleaning industry work in open-loop working mode, that is, the output parameters of the ultrasonic generator cannot change with the changes in the cleaning environment. In particular, the changes in the cleaning liquid temperature, liquid level, and the cleaning solvent itself in the cleaning tank will cause the overall load to change. All of these will cause a large difference in the output power of the ultrasonic generator, resulting in unstable cleaning effects. For example:

[0008] Chinese patent application CN202210988411.0 discloses a slot-type ultrasonic cleaning device for semiconductor wafer processing, which modifies the vibration of the internal connector, but does not modify the vibration received by the annular connector. The two vibrations converge efficiently due to the inconsistency of the vibrations when they intersect, so that the parts of the wafer in the two different vibrations can be cleaned by different ultrasonic vibrations, and the vibration at the intersection of the vibrations is completely different because the directions of the two vibrations are completely different, so that the vibration at the intersection disturbs the water more violently, thereby cleaning the surface of the wafer more thoroughly. However, in the cleaning process, this method uses the high energy generated by the collision of the wave bands when the sound waves of the ultrasonic vibrations intersect to flush and clean the wafer. During the cleaning process, the disturbance of the water body is not easy to control, and the cleaning effect on the wafer is not good at the part with a smaller degree of disturbance; excessive disturbance may cause damage to the microstructure of the wafer, causing deformation of the wafer structure, and affecting the performance of the wafer.

[0009] Chinese patent application CN202111622810.7 proposes a megasonic emission device and an acoustic wave cleaning system for wafer cleaning. The device includes a shell and a transducer; the transducer is connected to the inner wall of the shell away from the oscillator, and a gap is provided between the transducer and the oscillator so that the transducer and the oscillator will not fall off. However, this method has too many transducers and shells, and is restricted by the wall of the container. The scattering and reflection of the wall on the ultrasonic wave affects the actual ultrasonic sound intensity and waveform.

[0010] There are many improved technologies. For example, most of the methods for achieving non-destructive cleaning using ultrasonic cleaning devices mainly involve adding different structures to selectively remove non-perpendicular ultrasonic / megasonic energy.

[0011] Including but not limited to:

[0012] Chinese patent application 202210153983.7 discloses a system and method for measuring cavitation intensity of ultrasonic cleaning transducer, the system includes an ultrasonic cleaning transducer for ultrasonic cleaning; a measuring water tank for placing the ultrasonic cleaning transducer; a signal source for outputting a single-frequency continuous signal for the ultrasonic cleaning transducer and making the ultrasonic cleaning transducer output an ultrasonic signal at a low power; a power amplifier for amplifying the signal of the signal source; a hydrophone for scanning and measuring the sound pressure on a straight line perpendicular to the center of the ultrasonic cleaning transducer radiation surface. A motion control system for controlling the movement of the hydrophone; and a data acquisition and analysis system for signal acquisition and data analysis.

[0013] In addition, Chinese patent application CN201610740883.9 discloses a non-destructive ultrasonic / megasonic cleaning device for pattern wafers, in which an ultrasonic / megasonic generating mechanism and a bottom quartz component are provided in a sealed cavity of a shell, and the ultrasonic / megasonic energy whose propagation direction is not perpendicular to the wafer surface direction can be selectively removed through a quartz micro-resonance cavity array, and the ultrasonic / megasonic energy on the surface of the pattern wafer is evenly distributed through the dynamic change of the distance between the bottom quartz sheet and the surface of the pattern wafer, so that any area within the entire pattern wafer range can be uniformly and non-destructively cleaned within a certain cleaning time. However, the use of a quartz micro-resonance cavity array to selectively remove ultrasonic / megasonic energy that is not perpendicular to the wafer surface in the above-mentioned patent helps to reduce damage to the pattern wafer, but it also causes a loss of part of the ultrasonic energy. This may reduce the overall cleaning efficiency, requiring the device to generate higher initial energy to compensate for the loss, thereby increasing energy consumption. Although the design is intended to remove ultrasonic / megasonic energy that is not perpendicular to the wafer surface direction, due to physical limitations in actual operation, it may not be possible to completely eliminate this energy. This unremoved wave energy will produce interference effects on the wafer surface, which not only increases unnecessary energy loss, but may also cause cleaning non-uniformity. The non-destructive cleaning device may be optimized for a specific type or size of patterned wafers, but due to the diversity of wafer patterns and materials, the device may not provide accurate cleaning results in all cases. For example, different wafer surface characteristics such as roughness and material hardness may cause changes in cleaning results, making it impossible for the same equipment to achieve accurate cleaning for all wafer types. Summary of the invention

[0014] The present invention aims to solve the above problems and technical requirements. The present invention proposes a wafer non-destructive composite ultrasonic cleaning system and its working and control method, aiming to solve the problem of difficulty in regulating the cavitation negative pressure during the wafer cleaning process and overcome the defect that it is difficult to determine the cleaning power in the traditional ultrasonic cleaning device. It improves the cleaning efficiency, avoids the damage to the wafer microstructure caused by the traditional cleaning method, ensures the purity of the wafer surface, and ensures that the performance and structure of the transistor are not damaged.

[0015] To this end, the present invention discloses a wafer non-destructive composite ultrasonic cleaning system, comprising an ultrasonic generating module, an acoustic wave acquisition module, a clamping bracket, a water tank, a water pressure acquisition module, a data processing and analysis module, a cleaning liquid management module and a control module; the ultrasonic generating module comprises a power oscillation module, a signal amplification module, an impedance matching module and a transducer module; the transducer module is arranged at one side of the water tank, and a water pressure acquisition module is arranged at the other side of the water tank; a clamping bracket is arranged at the upper side of the water tank; the transducer module is connected to the control module through the acoustic wave acquisition module and the data processing and analysis module in sequence, and the control module is connected to the transducer module in series through the power oscillation module, the signal amplification module and the impedance matching module in sequence to perform signal transmission and conversion; a cleaning liquid management module is installed on the outer wall of the water tank; the lower end of the clamping bracket extends into the water tank; the data processing and analysis module adopts a cavitation noise spectrum analysis method according to the ultrasonic cavitation effect and the cleaning liquid working condition in the water tank collected in real time by the acoustic wave acquisition module and the water pressure acquisition module, and the cleaning effect of the wafer surface clamped at the lower end of the clamping bracket, to timely adjust and control the working state of the transducer module; a digital-to-analog converter DAC and a voltage-controlled oscillator VCO are also installed in the ultrasonic generating module. The workflow includes:

[0016] 1) Pour cleaning liquid into the water tank and use a clamping bracket to clamp the wafer;

[0017] 2) Immerse the wafer below the level of the cleaning solution and adjust the portion of the wafer to be cleaned to the side where the transducer module emits sound waves;

[0018] 3) The power oscillation module sends an electrical signal of a preset voltage to the signal amplification module and the impedance matching module. After amplification by the signal amplifier and impedance matching, the signal is received by the highly focused ultrasonic sensor of the transducer module and converted into an acoustic signal of a specific frequency;

[0019] 4) The transducer module emits an acoustic signal and generates ultrasonic cavitation in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the wafer surface.

[0020] The power oscillation module includes an input unit for setting the power and frequency working range of the power oscillation module, a control unit for adjusting the output frequency of the PWM signal according to the instruction input by the input unit, a power generation unit for power amplification and inversion of the PWM signal input by the control unit, and a matching unit for receiving the electrical signal output by the power generation unit and converting the electrical signal into ultrasonic waves. The input unit, the control unit, the power generation unit and the matching unit are electrically connected in sequence. In addition, a sampling unit is also included, the input end of the sampling unit is connected to the battery cell of the matching unit, and the output end of the sampling unit is electrically connected to the control unit. After the power oscillation module is started, the input The unit input setting includes instructions for preset values ​​such as the output power, frequency, start and stop information of the power oscillation module, and then the control unit receives the start signal and selects the middle frequency of the frequency range according to the instruction input by the input unit, and transmits it to the power generation unit through the PWM signal. The power generation unit sends the signal to the matching unit through power amplification and inversion. The matching unit and the cleaning sink form a resonant circuit to generate ultrasonic waves for cleaning. At the same time, the current and voltage signals of the matching unit are collected through the sampling unit, and the corresponding power value is obtained through the multiplier and fed back to the control unit; the control unit collects the feedback power value through the AD port and compares it with the power input by the input unit. If the two values ​​are not equal, the control unit adjusts the output PWM frequency; by adjusting the PWM frequency, comparing the input power and the actual power and then adjusting again, the input power is gradually approached, and finally a constant power output is achieved; it should be pointed out that the maximum range of the PWM frequency adjustment is the frequency range of the input unit input; the sampling unit includes a current transformer, a voltage transformer and a multiplier circuit, the current transformer collects the current signal of the matching unit and inputs it into the multiplier circuit, the voltage transformer collects the voltage signal of the matching unit and inputs it into the multiplier circuit, and the multiplier obtains the corresponding power value according to the current signal and the voltage signal and feeds it back to the control unit; the input unit includes a function button and a display, the function button is connected to the I / O port of the control unit, and the display communicates with the control unit via the SPI bus; the power generation unit includes a half-bridge inverter circuit composed of a MOS tube and a MOSFET; the matching unit includes a resonant circuit composed of an inductor and a transducer; the control unit is a single-chip microcomputer.

[0021] The cleaning liquid management module includes a liquid level sensor and a liquid replenishing system, which are used to monitor and adjust the liquid level of the cleaning liquid in real time; the cleaning liquid management module structure includes: a liquid storage unit, a concentration liquid level detection unit, a control unit and an execution unit connected in sequence, the liquid storage unit is used to store the cleaning liquid; the concentration liquid level detection unit is used to detect the concentration and liquid level of the cleaning liquid in the liquid storage unit, and transmit the detected concentration data and liquid level data to the control unit; the control unit is used to generate a corresponding control signal according to the concentration data and liquid level data, and send the control signal to the execution unit; the execution unit is used to execute the actions of discharging the cleaning liquid of the liquid storage unit, replenishing the chemical agent of the liquid storage unit, replenishing the water of the liquid storage unit, replacing the cleaning liquid of the liquid storage unit, recovering the cleaning liquid of the reaction chamber, and supplying liquid to the reaction chamber according to the control signal.

[0022] The data processing and analysis module is used to receive real-time data from the sound wave acquisition module and the water pressure acquisition module, and use the built-in algorithm of the control module to process and analyze the sound wave and pressure data; the module feeds back the status of the cleaning process in real time, automatically sends control instructions to the control module, and adjusts the voltage, frequency and other parameters of the sound wave emission device to ensure the cleaning effect; the data processing and analysis module is used for signal acquisition and data analysis, and through the analysis of the cavitation noise spectrum, the harmonic noise level of the corresponding harmonic generated by cavitation is calculated by line spectrum extraction; the data processing and analysis module structure includes a peak detection circuit, a low peak coupling circuit, and a The peak detection circuit detects the signal in the data transmission channel of the Internet of Things in real time. When the peak value is less than the lower limit standard signal of 0.5V, the low peak signal enters the low peak coupling compensation circuit, performs difference operation with the +5V upper limit standard signal, and is coupled to the peak detection circuit. When the peak value is higher than or equal to the +5V upper limit standard signal, the three-stage step-by-step conduction circuit composed of transistors Q1, Q2, and Q3 is turned on step by step. The step-by-step conduction of the first to third stage transistors can change the amplification factor of the proportional amplifier circuit with the operational amplifier AR3 as the core. The voltage stabilization circuit outputs a 0.5V~+5V standard signal after voltage stabilization.

[0023] The control module is composed of a PLC or an embedded controller, which can automatically adjust the operation of the power oscillation module, the sound wave acquisition module, the water pressure acquisition module, the cleaning liquid management module and the clamping bracket according to the collected sound wave, pressure and liquid level data; through real-time feedback, the control module control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, ensuring the efficiency and stability of the cleaning process. The control module is composed of a PLC or an embedded controller, which can automatically adjust the operation of the power oscillation module, the sound wave acquisition module, the water pressure acquisition module, the cleaning liquid management module and the clamping bracket according to the collected sound wave, pressure and liquid level data. Through real-time feedback, the control module control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, ensuring the efficiency and stability of the cleaning process.

[0024] Furthermore, to achieve the above object, the present invention is configured as follows:

[0025] In particular, the sound wave collection module is a multi-point collection device that collects and analyzes sound pressure and sound wave signals at multiple points simultaneously.

[0026] In particular, the clamping bracket is equipped with a position sensor and an electric actuator to automatically adjust the position of the clamping bracket to ensure that the wafer surface is in the optimal cleaning area.

[0027] In particular, the signal amplification module includes an automatic gain control function, and the amplification factor is adjusted by the control module; the signal amplification module structure includes a signal amplifier and a power supply module, the power supply module is electrically connected to the signal amplifier, the power supply module includes a power adapter and a battery, the power adapter is electrically connected to two external power supplies at the same time, the battery is electrically connected to the power adapter, and the power adapter is provided with a storage circuit and a switch for switching the two external power supplies. The switch can switch the two external power supplies, so that when one of the external power supplies fails to supply power, the other external power supply can continue to supply power to the signal amplifier. When the two external power supplies fail to supply power at the same time, the storage circuit supplies power to the signal amplifier at the first time, and then the battery continues to supply power to the signal amplifier, ensuring that the signal amplifier always maintains a normal use state without interruption time, making the use of the signal amplification device more reliable.

[0028] In particular, the transducer module has temperature compensation and automatic calibration functions, and can automatically adjust under different environmental conditions to ensure the accurate conversion and emission of sound signals; the transducer module receives electrical signals of different periods, converts them into sound signals of corresponding frequencies and emits them; a high-focus ultrasonic sensor is arranged in the transducer module, and the high-focus ultrasonic sensor has an outer diameter of 64mm and a focal length of 63.2mm.

[0029] In particular, the impedance matching module includes three varactor diodes and at least one PI-type circuit with a fixed inductor; the varactor diodes perform impedance adjustment according to a bias voltage.

[0030] In particular, the acoustic wave acquisition module has an automatic pressure calibration function, which can automatically calibrate the pressure sensor according to the characteristics of the cleaning fluid; the acoustic wave acquisition module has waveform analysis and intelligent filtering functions, which can automatically adjust under different environmental conditions to ensure the accurate conversion and emission of acoustic signals; the acoustic wave acquisition module has the function of collecting acoustic signals and outputting acoustic signal waveforms; the acoustic wave acquisition module is a multi-point acquisition device, which simultaneously collects and analyzes the sound pressure and acoustic wave signals of multiple points.

[0031] The cleaning and control methods of the wafer non-destructive composite ultrasonic cleaning system include:

[0032] (a) A cleaning method comprising the following steps:

[0033] (1) Pour cleaning liquid into the water tank, use the clamping bracket to clamp the wafer, and monitor the cleaning liquid level in real time through the cleaning liquid management module. The module detects the liquid level of the cleaning liquid through the liquid level sensor. When the liquid level is lower than the set value, the control system automatically triggers the liquid replenishment system to keep the cleaning liquid at an appropriate level;

[0034] (2) Immerse the wafer in the cleaning liquid and adjust the part of the wafer to be cleaned to the side where the transducer emits sound waves. Through the automatic positioning of the clamping bracket, the position sensor detects the size and position of the wafer, and the control system automatically adjusts the height and angle of the clamping bracket based on the feedback, so that the wafer surface is always located in the optimal cleaning area;

[0035] (3) The sound wave generating device emits an electrical signal of a preset voltage, which is received by the transducer device and converted into a sound signal of a specific frequency after being amplified and impedance matched by the signal amplifying device. The sound wave generating device emits an electrical signal of a preset voltage according to the command of the control system. The signal is amplified by the signal amplifying device, and after the signal transmission is optimized by the impedance matching device, it is transmitted to the transducer device for sound signal conversion. The control system monitors the feedback signals from the sound wave collecting device and the water pressure collecting device in real time, and automatically adjusts the voltage, transmission frequency and gain value to ensure that the ultrasonic wave maintains the best transmission conditions during the entire cleaning process;

[0036] (4) The transducer device emits an acoustic signal, and ultrasonic cavitation occurs in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the wafer surface. During the cleaning process, the water pressure collection device and the acoustic wave collection device monitor the acoustic pressure and acoustic signal in real time, and the control system automatically adjusts the intensity and frequency of the acoustic wave emission based on the feedback to ensure the stability and efficiency of the cleaning effect.

[0037] (b) The control method mainly controls the preset voltage and includes the following steps:

[0038] (1) Pour cleaning liquid into the water tank, use the clamping bracket to clamp the wafer, and place the water pressure acquisition device in the cleaning liquid. At this time, the control system will monitor the pressure environment of the cleaning liquid through the water pressure acquisition device and prepare to start the acoustic wave emission process;

[0039] (2) Adjust the position of the water pressure collection device. The control system automatically adjusts the probe position of the water pressure collection device through feedback signals to ensure that it is accurately positioned in the sound wave emission area of ​​the transducer device. This step is crucial to ensure that the water pressure collection device can effectively capture the sound pressure data generated during the sound wave emission process;

[0040] (3) Emitting original sinusoidal electrical signal pulses: The control system emits 3-5 cycles of sinusoidal electrical signal pulses through the sound wave generating device according to the preset voltage parameters. The electrical signal is amplified by the signal amplifying device and then adjusted by the impedance matching device to reduce reflection and loss and ensure transmission efficiency. Finally, the signal is received by the transducer and converted into a sound wave signal of the corresponding frequency;

[0041] (4) The transducer device emits a sound wave signal, causing ultrasonic cavitation in the cleaning liquid. At this time, the water pressure collection device begins to detect the negative pressure changes in the sound wave emission area. The water pressure collection device feeds back the measured negative pressure data to the control system in real time. Based on this feedback, the control system can automatically adjust the voltage, frequency and other emission parameters of the sound wave generating device to ensure the effectiveness of the cavitation phenomenon;

[0042] (5) Monitoring and processing of reflected sound wave signals: The sound wave acquisition device is placed on one side of the transducer device to capture the sound wave reflection signal. The sound wave acquisition device receives the reflection signal in real time and outputs the corresponding waveform data. The control system analyzes the waveform to determine whether the amplitude of the reflected waveform has reached the preset threshold. If the amplitude of the reflected waveform exceeds 1.5 times that when no cavitation occurs, the control system automatically determines that cavitation has occurred;

[0043] (6) Automatic determination of cavitation: The control system determines whether cavitation has occurred by comparing the amplitude of the reflected waveform with the preset amplitude threshold. If the amplitude of the reflected signal reaches or exceeds the set 1.5 times threshold, the system confirms that cavitation has occurred and automatically records the number of cavitation occurrences. If the threshold is not reached, the system determines that cavitation has not occurred and adjusts the voltage or frequency transmission parameters.

[0044] (7) Calculation of cavitation probability: The system automatically calculates the cavitation probability based on the number of cavitation occurrences and the number of pulses emitted. This probability is used to determine the effectiveness of the cleaning process. The system can adjust in real time based on the frequency of cavitation to ensure that the cleaning effect reaches the best level.

[0045] (8) Voltage and frequency adjustment: According to the preset voltage interval, the system gradually increases or decreases the electrical signal voltage of the acoustic wave generator. After each voltage adjustment, the system will repeat steps (3) to (7) to automatically measure the cavitation probability under different negative pressure conditions.

[0046] (9) Generate cavitation probability curve and determine optimal cleaning parameters: The system generates a cavitation probability curve based on the cavitation probability data under different voltages and negative pressures. With negative pressure as the horizontal axis and cavitation probability as the vertical axis, the system automatically analyzes and obtains the negative pressure value when the cavitation probability reaches 50%, which is the cavitation threshold. The acoustic wave emission voltage corresponding to the negative pressure at this time will be set as the preset voltage of the cleaning system to ensure the best cleaning efficiency at this voltage.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] By accurately collecting the cavitation negative pressure during the cleaning process, the influence of the wall of the water tank container can be reduced. The occurrence of cavitation under different pressures is detected, and the cavitation threshold of the cleaning liquid and the wafer is obtained, and then precise control under cavitation cleaning is implemented. The optimized ultrasonic vibration can penetrate into the tiny gaps and structures on the surface of the wafer, effectively remove the hard-to-reach pollutants, improve the cleaning efficiency, and reduce the structural damage to the surface of the wafer during the cleaning process. It has high flexibility and adaptability. Ultrasonic cleaning has relatively low energy consumption, which helps to save energy and reduce consumption, and can be applied to the cleaning needs of wafers of different sizes and types. The relative positions of the acoustic wave acquisition module, the clamping bracket and the water pressure acquisition module are reasonably set, the operation is simple, and it is easy to implement; the intensity of the cavitation activity generated by the transducer module is more clearly and intuitively measured and controlled. Not only must the purity of the wafer surface be ensured, but also the processing quality and structure of the wafer must be protected from damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The following drawings are for illustration only and should not be construed as limiting the present invention in any way. By referring to the following drawings, readers can understand the embodiments of the present invention and further understand the advantages and technical features of the present invention.

[0050] Figure 1 Schematic diagram of the structure of an ultrasonic transmitting system for wafer cleaning in an embodiment of the present invention.

[0051] Figure 2 Schematic diagram of the working process of an embodiment of the present invention.

[0052] Figure 3 Schematic diagram of the structure of the ultrasonic generating module in the embodiment of the present invention.

[0053] Figure 4 Schematic diagram of the structure of a signal amplification module in an embodiment of the present invention.

[0054] Figure 5Schematic diagram of an impedance matching module and circuit structure in an embodiment of the present invention.

[0055] Figure 6 Schematic diagram of the structure of the energy conversion module in an embodiment of the present invention.

[0056] Figure 7 Schematic diagram of a sound wave collection module in an embodiment of the present invention.

[0057] Figure 8 Schematic diagram of the structure of a water pressure collection module in an embodiment of the present invention.

[0058] Fig. 9 Schematic diagram of the data processing and analysis module structure in an embodiment of the present invention.

[0059] Fig.10 Schematic diagram of the circuit structure of the data processing and analysis module in an embodiment of the present invention.

[0060] Fig.11 Schematic diagram of the cleaning liquid management module in an embodiment of the present invention.

[0061] Reference numerals include:

[0062] 1-power oscillation module, 2-signal amplification module, 3-impedance matching module, 4-transducer module, 5-sound wave acquisition module, 6-clamping bracket, 7-water tank, 8-water pressure acquisition module, 9-wafer, 10-data processing and analysis module, 11-cleaning liquid management module, 12-control module. DETAILED DESCRIPTION

[0063] It should be noted that:

[0064] The terms "comprise", "comprises", "having" and any variations thereof are intended to cover other possible options under the same logic that are not listed. For example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or apparatus.

[0065] In the description of the present invention, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0066] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0067] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only embodiments of a part of the present invention, rather than all embodiments.

[0068] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. In the event of a conflict, the definitions in this specification shall prevail.

[0069] Although ultrasonic cleaning technology performs well in improving the efficiency of contaminant removal, it also inevitably brings about the problem of wafer damage. This phenomenon is mainly due to the fact that when the ultrasonic wave propagates, its energy acts on the surface of the wafer 9, and the lateral force generated is often greater than the surface adhesion of the wafer 9, resulting in the destruction of the surface structure of the wafer 9 during the cleaning process. In the process of using ultrasonic cleaning, it is impossible to accurately control the energy of the sound wave emission to achieve non-destructive cleaning of the patterned wafer.

[0070] Ultrasonic non-destructive wafer cleaning uses the cavitation effect of ultrasound in the cleaning liquid to generate powerful shock waves and microjets to clean the wafer surface non-contactly. This cleaning method removes pollutants on the wafer surface through physical action without the need to use corrosive chemical reagents such as strong acids and alkalis, thus avoiding the damage and pollution problems that may be caused by chemical cleaning. Ultrasonic non-destructive wafer cleaning is an efficient, environmentally friendly and non-destructive cleaning method that has broad application prospects and important practical value in the field of semiconductor manufacturing.

[0071] Among the many practical applications of power ultrasound, ultrasonic cleaning is one of the most widely used. Ultrasonic cleaning utilizes the physical effect, chemical effect, thermal effect and cavitation effect of ultrasound, among which the cavitation effect plays a key role. When ultrasound acts on the liquid medium in the cleaning tank, pressure fluctuations will be generated in the sound field in the cleaning tank due to the effect of driving ultrasound. As the power of the ultrasonic transducer increases, the pressure fluctuations in the sound field also increase, and negative pressure is generated in some areas, and cavitation occurs. The expansion, contraction, and collapse of cavitation bubbles in the cleaning tank will generate mechanical impact forces in the surrounding area, peeling off impurities, oil stains and other contaminants on the surface of the cleaned device to achieve the cleaning effect. The air cavity and bubbles formed under the action of the alternating pressure field (acoustic field) are called acoustic cavitation, and such air cavitation and bubbles are called cavitation bubbles. Acoustic cavitation can include a cavitation or a group of moving cavitation bubbles formed by the excitation of the acoustic field. According to the life span and radius change rate of the cavitation bubble in the liquid medium, there are two main types of acoustic cavitation: transient cavitation and steady-state cavitation. The bubbles of steady-state cavitation exist for a long time and are individually dispersed in the water tank. In the acoustic field environment of an ultrasonic cleaning tank, after bubbles are generated, most of them oscillate with a small amplitude at a fixed position. A small number of bubbles oscillate with a large amplitude, or burst after moving to the boundary in the acoustic field. Transient cavitation is related to the cavitation effect, which will produce extreme physical conditions and jet phenomena in the liquid medium. Although it promotes cleaning, its destructive power is also very strong and needs attention. Common acoustic cavitation includes transient cavitation.

[0072] The cavitation threshold is the minimum pressure amplitude that can cause cavitation in the liquid medium, which reflects the difficulty of cavitation. The higher the cavitation threshold, the higher the required pressure amplitude and the more difficult it is to cause cavitation; conversely, it is easier. Under ideal conditions, the cavitation threshold that overcomes the van der Waals force and causes cavitation is called the ideal cavitation threshold. In reality, there are tiny impurities in the liquid, and there are gaps on these impurity particles, and there is a small amount of gas in the gaps. The gas in the gaps between these impurity particles, the gas in the gaps on the container wall, and the microbubbles in the liquid are called cavitation nuclei, and the cavitation caused by the pressure fluctuations of the cavitation nuclei is called nucleated cavitation.

[0073] Cavitation noise is caused by the linear and nonlinear pulsation of cavitation bubbles, the formation and collapse of cavitation bubbles, and the interaction between cavitation bubbles when cavitation occurs, and it always accompanies the cavitation process. Under the action of high-power ultrasound, a large number of cavitation bubbles will be generated in the compact liquid medium, and they will pulsate with a large amplitude. The large-amplitude pulsation of cavitation bubbles is highly nonlinear, which makes the sound spectrum of the noise it radiates very complex, including harmonics, subharmonics, superharmonics and other components. The process of cavitation bubble collapse is more complicated than steady-state pulsation, which brings more complex spectral components. In steady-state cavitation, microflows appear around the bubbles due to the oscillation of bubbles and the expansion and contraction of bubble walls. At the same time, cavitation noise contains harmonics and subharmonics, and superharmonics will appear as the cavitation intensity increases. Transient cavitation usually appears in the form of clusters. Bubbles are generated and quickly burst, and the cycle repeats, forming a bubble cloud in a certain area. When transient cavitation occurs, broadband noise is generated. The cavitation noise must contain harmonics, subharmonics, superharmonics, and a continuous spectrum that symbolizes the existence of transient cavitation.

[0074] The cavitation noise spectrum analysis method is a method of obtaining the cavitation intensity by measuring and analyzing the cavitation noise. The generation of cavitation noise is an important feature of the liquid medium, that is, the cleaning liquid in the water tank 7 when cavitation occurs. Cavitation noise is caused by factors such as the linear and nonlinear pulsation of cavitation bubbles, the formation and collapse of cavitation bubbles, and the interaction between cavitation bubbles when cavitation occurs, and is always accompanied by the cavitation process. When ultrasonic cavitation occurs, the sound field is the superposition of the driving ultrasonic sound field and the cavitation noise. Because cavitation noise contains complex and diverse components, and these components come from different sources, measuring cavitation noise and analyzing the cavitation noise spectrum components can understand the various parts of the cavitation process, including the initiation and intensity of cavitation.

[0075] The principle of the present invention is that the data processing and analysis module 10 uses the cavitation noise spectrum analysis method to timely adjust the working state of the transducer module 4 according to the ultrasonic cavitation effect and the working condition of the cleaning liquid in the water tank 7 collected in real time by the sound wave collection module 5 and the water pressure collection module 8, as well as the surface cleaning effect of the wafer 9 clamped at the lower end of the clamping bracket 6. The intensity of the cavitation activity generated by the transducer module 4 can be more clearly and intuitively expressed, and the steady-state cavitation intensity and transient cavitation intensity of the cavitation generated by the ultrasonic cleaning of the transducer module 4 can be measured, so that the transducer module 4 is in the best working state.

[0076] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0077] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

[0078] Reference Figure 1 As shown, the wafer non-destructive composite ultrasonic cleaning system of the present invention includes an ultrasonic generating module, an acoustic wave acquisition module 5, a clamping bracket 6, a water tank 7, a water pressure acquisition module 8, a data processing and analysis module 10, a cleaning liquid management module 11 and a control module 12. The ultrasonic generating module includes a power oscillation module 1, a signal amplification module 2, an impedance matching module 3 and a transducer module 4. The transducer module 4 is arranged on one side of the water tank 7, and a water pressure acquisition module 8 is arranged on the other side of the water tank 7; a clamping bracket 6 is arranged on the upper side of the water tank 7; the transducer module 4 is connected to the control module 12 in turn through the acoustic wave acquisition module 5 and the data processing and analysis module 10, and the control module 12 is connected to the transducer module 4 in series in turn through the power oscillation module 1, the signal amplification module 2 and the impedance matching module 3 for signal transmission and conversion. The cleaning liquid management module 11 is installed on the outer wall of the water tank 7. The lower end of the clamping bracket 6 extends into the cleaning liquid in the water tank 7 and clamps the wafer 9.

[0079] The content of the present invention can be more easily understood by selecting the following preferred implementation methods of the present invention and the embodiments included. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those of ordinary skill in the art to which the present invention belongs. When there is a conflict, the definition in this specification shall prevail.

[0080] Embodiment 1: As attached Figure 2 As shown in the figure, the working process of the wafer non-destructive composite ultrasonic cleaning system includes:

[0081] 1) Pour cleaning liquid into the water tank 7 and use the clamping bracket 6 to clamp the wafer 9;

[0082] 2) Immerse the wafer 9 in the cleaning liquid, and adjust the portion of the wafer 9 to be cleaned to the side where the transducer module 4 emits sound waves;

[0083] 3) The power oscillation module 1 sends an electrical signal of a preset voltage to the signal amplification module 2 and the impedance matching module 3. After amplification by the signal amplifier and impedance matching, the signal is received by the highly focused ultrasonic sensor of the transducer module 4 and converted into an acoustic signal of a specific frequency;

[0084] 4) The transducer module 4 emits an acoustic signal and causes ultrasonic cavitation in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the surface of the wafer 9 .

[0085] The ultrasonic generator module is also equipped with a digital-to-analog converter DAC and a voltage-controlled oscillator VCO. In particular, the ultrasonic generator module adjusts the signal voltage amplitude between 2mVpp and 10Vpp, and can output a frequency of 1uHz to 10MHz. The cavitation threshold of the ultrasonic generator module is 1.5Mpa, where the preset voltage is 0.32Vpp.

[0086] In the embodiment of the present invention, the power oscillation module 1 adopts an automatic voltage control mode, and automatically adjusts the signal voltage through the control module 12 to adapt to different cleaning requirements. The power oscillation module 1 can generate electric pulse signals of different periods, and can change the signal size by adjusting the voltage. Figure 3 As shown, the power oscillation module 1 includes an input unit for setting the power and frequency working range of the power oscillation module 1, a control unit for adjusting the output frequency of the PWM signal according to the instruction input by the input unit, a power generation unit for power amplification and inversion of the PWM signal input by the control unit, and a matching unit for receiving the electric signal output by the power generation unit and converting the electric signal into ultrasonic wave. The input unit, the control unit, the power generation unit and the matching unit are electrically connected in sequence. In addition, a sampling unit is also included. The input end of the sampling unit is connected to the battery cell of the matching unit, and the output end of the sampling unit is electrically connected to the control unit. After the power oscillation module 1 is started, the input end of the sampling unit is connected to the matching unit battery cell, and the output end of the sampling unit is electrically connected to the control unit. The unit input setting includes instructions for preset values ​​such as the output power, frequency, start and stop information of the generator of the power oscillation module 1. Then, after receiving the start signal, the control unit selects the middle frequency of the frequency range and transmits it to the power generating unit through the PWM signal according to the instructions input by the input unit. The power generating unit sends the signal to the matching unit through power amplification and inversion. The matching unit and the cleaning sink form a resonant circuit to generate ultrasonic waves for cleaning. At the same time, the current and voltage signals of the matching unit are collected through the sampling unit, and the corresponding power value is obtained through the multiplier and fed back to the control unit; the control unit collects the feedback power value through the AD port and compares it with the power input by the input unit. If the two values ​​are not equal, the control unit adjusts the output PWM frequency; by adjusting the PWM frequency, comparing the input power and the actual power and then adjusting again, the input power is gradually approached, and finally a constant power output is achieved; it should be pointed out that the maximum range of the PWM frequency adjustment is the frequency range of the input unit input; the sampling unit includes a current transformer, a voltage transformer and a multiplier circuit, the current transformer collects the current signal of the matching unit and inputs it into the multiplier circuit, the voltage transformer collects the voltage signal of the matching unit and inputs it into the multiplier circuit, and the multiplier obtains the corresponding power value according to the current signal and the voltage signal and feeds it back to the control unit; the input unit includes a function button and a display, the function button is connected to the I / O port of the control unit, and the display communicates with the control unit through the SPI bus; the power generation unit includes a half-bridge inverter circuit composed of a MOS tube and a MOSFET; the matching unit includes a resonant circuit composed of an inductor and a transducer; the control unit is a single-chip microcomputer; in particular, the power supply oscillation module 1 selects 3 to 5 cycles of sinusoidal electrical signal pulses with a frequency of 1.1Hz.

[0087] When the power oscillation module 1 is started, the input unit inputs the preset values ​​including the output power, frequency, start and stop information of the ultrasonic generator, etc., and then the control unit receives the start signal and selects the middle frequency of the frequency range according to the input command of the input unit, and transmits it to the power generation unit through the PWM signal. The power generation unit sends the signal to the matching unit through power amplification and inversion. The matching unit and the cleaning water tank form a resonant circuit to generate ultrasonic waves for cleaning. At the same time, the current and voltage signals of the matching unit are collected through the sampling unit, and the corresponding power value is obtained through the multiplier and fed back to the control unit. The control unit collects the feedback power value through the AD port and compares it with the power input of the input unit; if the two values ​​are not equal, the control unit adjusts the output PWM frequency; by adjusting the PWM frequency, comparing the input power and the actual power, it gradually approaches the input power and finally achieves constant power output; it should be pointed out that the maximum range of PWM frequency adjustment is the frequency range of the input unit input.

[0088] In the embodiment of the present invention, the signal amplification module 2 includes an automatic gain control function, and the amplification factor is adjusted by the control module to ensure the stability of the signal strength. The signal amplification module 2 amplifies the electrical signal emitted by the power supply oscillation module 1 and has an adjustable amplification factor. Figure 4 As shown, the structure of the signal amplification module 2 includes a signal amplifier and a power supply module, the power supply module is electrically connected to the signal amplifier, the power supply module includes a power adapter and a battery, the power adapter is electrically connected to two external power supplies at the same time, the battery is electrically connected to the power adapter, and the power adapter is provided with a storage circuit and a switch for switching the two external power supplies. The switch can switch the two external power supplies, so that when one of the external power supplies fails to supply power, the other external power supply can continue to supply power to the signal amplifier. When the two external power supplies fail to supply power at the same time, the storage circuit supplies power to the signal amplifier at the first time, and then the battery continues to supply power to the signal amplifier, ensuring that the signal amplifier always maintains a normal use state without interruption time, so that the use of the signal amplification device is more reliable. In particular, the operating frequency of the signal amplification module 2 is 10kHz to 10MHz, and the maximum output amplitude is 28Vpp.

[0089] In the embodiment of the present invention, further, as shown in the attached Figure 5 As shown, the impedance matching module 3 can prevent the transmitted electrical signal from generating signal reflection, thereby ensuring accurate signal transmission. The impedance matching module 3 includes three varactor diodes and at least one PI-type circuit with fixed inductance; the varactor diodes adjust impedance according to the bias voltage. Full-range automatic impedance matching can be achieved, and it has the advantages of simple implementation, small size and low cost. In particular, the maximum operating frequency of the impedance matching module 3 is 2 GHz.

[0090] In the embodiment of the present invention, the transducer module 4 has temperature compensation and automatic calibration functions, and can automatically adjust under different environmental conditions to ensure accurate conversion and emission of acoustic signals. Furthermore, the transducer module 4 receives electrical signals of different periods, converts them into acoustic signals of corresponding frequencies, and emits them. The structure and working principle of the transducer module 4 are shown in the attached figure. Figure 6 As shown, the service life is extended and safety is improved.

[0091] In the above, the transducer module 4 is a transducer, which refers to a device that converts electrical energy and acoustic energy into each other. It is often used in echo sounders, Doppler odometers and acoustic correlation odometers. The main performance indicators of the transducer module 4 are: operating frequency, bandwidth, electroacoustic frequency, impedance at resonant frequency, transmission beam width, directivity and sensitivity, etc. According to the physical properties and the materials used, transducers can be divided into two categories: magnetostrictive transducers and electrostrictive transducers. The transducer that converts acoustic energy into electrical energy is the receiving transducer. The transducer module 4 that converts electrical energy into acoustic energy is called a transmitting transducer. The transmitting and receiving transducers are usually used separately, but one can also be shared. The former uses the magnetostrictive effect of ferromagnetic materials and is often made of nickel or nickel-iron alloy; the latter uses the electrostrictive effect and piezoelectric effect and is often made of dielectric electrical materials such as barium titanate ceramics and lead titanate ceramics. Preferably, a high-focus ultrasonic sensor is provided in the transducer module 4, the high-focus ultrasonic sensor has an outer diameter of 64 mm, a geometric focal length of 63.2 mm, a rated operating frequency of 1.1 MHz, a central focus area of ​​4 mm2, and a theoretical central magnification of 40.09 times. The high-focus ultrasonic sensor is installed in the cleaning liquid at the lower end of the transducer module 4 in the water tank 7, the front end sound-emitting concave surface of the high-focus ultrasonic sensor faces the wafer 9, and the wafer 9 is in the focal area of ​​the high-focus ultrasonic sensor. The directivity of the high-focus ultrasonic sensor can be characterized by beam width or half-diffusion angle.

[0092] In an embodiment of the present invention, the acoustic wave acquisition module 5 has the function of collecting acoustic signals and outputting acoustic signal waveforms. The acoustic wave acquisition module 5 has an automatic pressure calibration function, and can automatically calibrate the pressure sensor according to the characteristics of the cleaning fluid. The acoustic wave acquisition module 5 has waveform analysis and intelligent filtering functions, and can automatically adjust under different environmental conditions to ensure accurate conversion and transmission of acoustic signals. The acoustic wave acquisition module 5 has the function of collecting acoustic signals and outputting acoustic signal waveforms. The acoustic wave acquisition module 5 is a multi-point acquisition device, which simultaneously collects and analyzes the sound pressure and acoustic wave signals of multiple points. Further, as shown in the attached Figure 7As shown, the structure of the acoustic wave collection module 5 includes a sleeve joint 501 with a through-hole structure inside, a stepped notch and a stepped groove that are conductive to the inside are arranged on the ring body of the sleeve joint 501, a piezoelectric component 507 is installed at the bottom of the stepped notch, an end cover 503 is fixedly arranged on the outside of the piezoelectric component 507, a convex ring is arranged on the inner bottom surface of the end cover 503, the convex ring is supported on the surface of the piezoelectric component 507, a wire passing groove is arranged in the convex ring close to the stepped groove, the wire passing groove is connected with the stepped groove after passing through the wire passing hole on the sleeve joint 501, a single-core socket 505 is installed in the small-diameter groove of the stepped groove, a socket cover 504 is fixedly installed in the middle-diameter groove of the stepped groove, and the top end of the single-core socket 505 extends to the inside of the socket cover 504 The end cover is on the outside and fixed with a nut 506. The wire of the piezoelectric component 507 passes through the wire groove and the wire hole and extends into the stepped groove and is connected to the positive pole at the upper end of the single-core socket 505. The end cover 503 and the sleeve joint 501 are clearance-matched. The sleeve joint 501, the end cover 503, the socket cover 504, the single-core socket 505 and the piezoelectric component 507 are all metal components; the piezoelectric component 507 includes a metal substrate, a piezoelectric ceramic sheet is pasted in the bottom groove of the metal substrate 512, and the negative end surface of the piezoelectric ceramic sheet is in contact with the bottom surface of the bottom groove of the metal substrate, a wire is connected to the positive end surface of the piezoelectric ceramic sheet, and the wire passes through the wire through hole of the metal substrate, and insulating paint is provided on the outer end surfaces of the piezoelectric ceramic sheet and the metal substrate. By using a metal-based piezoelectric component, the infiltrated gas can be released through the gap between the end cap and the sleeve joint, thus preventing the negative electrode of the piezoelectric component from being compressed and corroded by corrosive gases, effectively improving the life of the piezoelectric component and solving the problem of reduced sensitivity or even failure of the microphone caused by high-pressure gas leakage. In particular, the acoustic wave acquisition module 5 outputs a signal waveform with a sampling rate of 1GSa / s and a time base range of 50s to 10ns.

[0093] In the embodiment of the present invention, the clamping bracket 6 is used to clamp the wafer 9 and can move up and down. The clamping bracket 6 is equipped with a position sensor and an electric actuator to automatically adjust the position of the clamping bracket to ensure that the surface of the wafer 9 is in the optimal cleaning area. The accuracy of the movement of the clamping bracket 6 is 1mm.

[0094] In the embodiment of the present invention, the water pressure acquisition module 8 can detect the intensity of the sound pressure in the water. The water pressure acquisition module 8 has an automatic pressure calibration function, and can automatically calibrate the pressure sensor according to the characteristics of the cleaning fluid. The water pressure acquisition module 8 can be set as a multi-point acquisition device to collect and analyze the sound pressure and sound wave signals at multiple points at the same time. Figure 8As shown, the water pressure acquisition module 8 can detect the intensity of sound pressure in water. The water pressure acquisition module 8 includes a connection joint 82 that is detachably connected to the water pressure output nozzle 81 of the fire hydrant buckle water pressure tester, and a signal acquisition transceiver unit 83 that is detachably connected to the connection joint 82 to communicate with the water pressure output nozzle 81 of the fire hydrant buckle water pressure tester through the connection joint 82; a connection channel 821 that is connected to the water pressure output nozzle 81 of the fire hydrant buckle water pressure tester is provided on the connection joint 82, and a detection channel 832 that is connected to the connection channel 821 is provided on the signal acquisition transceiver unit 83, so that the detection water output from the water pressure output nozzle 81 of the fire hydrant buckle water pressure tester can be transported to the detection channel 832 through the connection channel 821; a pressure sensor 83 for detecting the water pressure in the detection channel is provided in the detection channel 832 of the signal acquisition transceiver unit 83. 33, and the signal acquisition transceiver unit 83 is also arranged with a pressure signal acquisition module 834, an AD conversion module 835 and a wireless communication transceiver module 836; the pressure signal output end of the pressure sensor 833 is connected to the signal acquisition end of the pressure signal acquisition module 834 for data transmission, so as to acquire the pressure signal; the output end of the pressure signal acquisition module 834 is connected to the data input end of the wireless communication transceiver module 836 through the AD conversion module 835 for data transmission, so as to convert the acquired pressure signal into digital form and send it to the wireless communication transceiver module 836 for external transmission; the instruction receiving end of the pressure sensor 833 is also connected to the data return end of the wireless communication transceiver module 836 for data transmission, so as to receive external pressure acquisition control instructions through the wireless communication transceiver module 836.When the water pressure collection module 8 collects the water pressure at the fire bolt buckle water pressure testing machine, first turn on the fire bolt buckle water pressure testing machine and preheat it for 3 minutes; then select the connecting joint 82 that is compatible with the fire bolt buckle water pressure testing machine, install the pressure sensor 8033 in the detection channel 832 of the signal collection and transceiver unit 83, and then connect the signal collection and transceiver unit 83 with the connecting joint 82, and finally connect the connecting joint 802 to the water pressure output nozzle 81 of the fire bolt buckle water pressure testing machine. At this time, the water pressure of the fire bolt buckle water pressure testing machine can be collected. When collecting the water pressure, first test the sealing and strength of the fire bolt buckle water pressure testing machine itself, and then The values ​​on the test machine and the pressure sensor are reset to zero. At this time, the fire bolt buckle water pressure tester is slowly pressurized. At this time, the test water will be output from the water pressure output nozzle 81 of the fire bolt buckle water pressure tester through the connecting channel to the detection channel 832. The test water output to the detection channel 832 applies pressure to the pressure sensor in the detection channel 832, so that the pressure of the pressure sensor 833 stabilizes to the first detection point, and then the fire bolt buckle water pressure tester is continuously pressurized until the upper limit of measurement. No less than 5 detection points are evenly selected from the zero point to the upper limit of measurement. When the pressure is increased to the upper limit of measurement, a return calibration is performed until the zero point. In this way, the water pressure collection at the fire bolt buckle water pressure tester is completed using the pressure sensor 833. After the pressure sensor 833 collects the pressure data, the pressure data collected by the pressure sensor 833 is transmitted to the pressure signal collection module 834, and the pressure signal collection module 834 further transmits the pressure data to the AD conversion module 835. The AD conversion module 835 performs analog-to-digital conversion on the received pressure data, and the pressure data converted into digital signals is further transmitted to the outside through the wireless communication transceiver module 836. At the same time, the command receiving end of the pressure sensor 833 is also connected to the data return end of the wireless communication transceiver module 836 for data transmission, so that the pressure collection control command can be sent to the pressure sensor 833 through the wireless communication transceiver module 836, so that the pressure sensor 833 completes the detection of pressure data at a specific detection point. The collected pressure data is used to determine whether the technical parameters of the fire bolt buckle water pressure tester meet the requirements. During the test, the tester inputs the maximum allowable error and other related data into the host computer data processing unit before the test. After the pressure data detected by the water pressure acquisition device is transmitted to the host computer data processing unit, it will be calculated, compared and analyzed with the maximum allowable error and other data stored in advance by AI technology. If the measured error is within the allowable error range, it is judged that the test result meets the standard, otherwise it is judged that it does not meet the standard. In particular, the water pressure acquisition module 8 is a needle hydrophone, and the negative pressure range that can be detected is 0 to 5MPa.

[0095] In the embodiment of the present invention, the data processing and analysis module 10 is used to receive real-time data from the sound wave acquisition device and the water pressure acquisition device, and use the built-in algorithm of the control system to process and analyze the sound wave and pressure data. The data processing and analysis module 10 feeds back the state of the cleaning process in real time, and automatically sends a control instruction to the control module to adjust the voltage, frequency and other parameters of the sound wave emission device to ensure the cleaning effect. The data processing and analysis module 10 is used for signal acquisition and data analysis, and calculates the harmonic noise level of the corresponding harmonic generated by cavitation by line spectrum extraction through cavitation noise spectrum analysis. According to the characteristics of ultrasonic cavitation and cavitation noise, the cavitation intensity is represented by the difference between the harmonic noise level corresponding to different types of cavitation and the harmonic noise level corresponding to the cavitation threshold, which more clearly and intuitively represents the intensity of the cavitation activity generated by the ultrasonic cleaning of the transducer module 4; the steady-state cavitation intensity and the transient cavitation intensity of the cavitation generated by the ultrasonic cleaning of the transducer module 4 are measured, and the ultrasonic cleaning power of the transducer module 4 can be adjusted accordingly to make it work in the best state; the cavitation intensity is represented by the spatial average of the harmonic noise level, which better represents the overall situation of the cavitation in the measuring tank 7.

[0096] Further, as attached Fig. 9As shown, the structure of the data processing and analysis module 10 includes a peak detection circuit, a low-peak coupling compensation circuit, and a feedback amplitude modulation circuit. The peak detection circuit detects the signal in the IoT data transmission channel in real time. When the peak value is less than the 0.5V lower limit standard signal, the low-peak signal enters the low-peak coupling compensation circuit, performs a difference operation with the +5V upper limit standard signal, and is coupled to the peak detection circuit. When the peak value is higher than or equal to the +5V upper limit standard signal, the three-stage step-by-step conduction circuit composed of transistors Q1, Q2, and Q3 is conducted step by step. The step-by-step conduction of the first to third stage transistors can change the amplification factor of the proportional amplifier circuit with the operational amplifier AR3 as the core, and the voltage stabilization circuit outputs a 0.5V~+5V standard signal after voltage stabilization. It can detect the peak value of the signal in the data transmission channel in real time, perform coupling compensation at low peaks, and adjust the proportion at high peaks, and output a stable 0.5V~+5V standard signal to the terminal server, effectively solving the problem that the signal distortion cannot be effectively received by the terminal server.The peak detection circuit detects the signal in the Internet of Things data transmission channel of the agricultural greenhouse data processing and analysis system, and the interference is filtered out by the π-type filter circuit composed of the inductor L1, the capacitor C1, and the capacitor C2, and then enters the peak detection circuit composed of the operational amplifier AR1, the operational amplifier AR2, the resistor R1, the resistor R2, the diode D1, the diode D2, and the capacitor C3. When the peak value is less than the 0.5V lower limit standard signal, the diode D1 is forward biased, and the low peak signal enters the low peak coupling compensation circuit. The low peak coupling compensation circuit enters the in-phase input terminal of the operational amplifier AR4 after voltage division and unidirectional conduction, and performs differential analysis with the +5V upper limit standard signal of the inverting input terminal. The output terminal of the operational amplifier AR4 outputs a difference voltage which is coupled to the non-inverting input terminal of the operational amplifier AR1 in the peak detection circuit. When the peak value is higher than or equal to the +5V upper limit standard signal, the diode D2 is forward biased, and the voltage of the operational amplifier AR2 follows and is output. After that, it is amplified by the proportional amplifier circuit with the operational amplifier AR3 as the core and output after voltage stabilization by the voltage stabilization circuit with the transistor Q4 as the core. The feedback amplitude modulation circuit collects the output signal after voltage stabilization and amplifies it proportionally. The greater the amplitude of the signal higher than the +5V upper limit standard signal, the more conduction stages the three-stage step-by-step conduction circuit composed of the transistors Q1, Q2, and Q3 will have. The step-by-step conduction of the first to third stage transistors can change the operational amplifier AR3 to The amplification factor of the core proportional amplifier circuit makes the output voltage stable between 0.5V and +5V standard signals; in the feedback amplitude modulation circuit, when the output signal after voltage stabilization is higher than the +5V upper limit standard signal, the potentiometer RW2 and the resistor R11 form a sampling circuit voltage trigger diode D5 to turn on, and the proportional amplifier circuit with the operational amplifier AR3 as the core amplifies and enters the three-stage step-by-step conduction circuit composed of transistors Q1, Q2, and Q3. When the output signal after voltage stabilization is 5.0V-5.7V, the transistor Q1 is turned on, the relay K1 coil is energized, the normally open contact is closed, and the resistor R15 is connected in parallel to the two ends of the feedback resistor R9 of the operational amplifier AR3, and the voltage is stabilized. When the output signal after voltage regulation is 5.8V-6.4V, transistors Q1 and Q2 are turned on, relays K1 and K2 coils are energized, and the normally open contacts are closed. Resistors R15 and R16 are connected in parallel to both ends of the feedback resistor R9 of op amp AR3. When the output signal after voltage regulation is higher than 6.4V, transistors Q1, Q2, and Q3 are turned on, relays K1, K2, and K3 coils are energized, and the normally open contacts are closed. Resistors R15, R16, and R17 are connected in parallel to both ends of the feedback resistor R9 of op amp AR3, thereby changing the amplification factor of the proportional amplifier circuit with op amp AR3 as the core, so that the output voltage is stabilized at a standard signal of 0.5V to +5V.

[0097] In the embodiment of the present invention, the cleaning liquid management module 11 is composed of a liquid level sensor and a liquid replenishment system, which is used to monitor and adjust the liquid level of the cleaning liquid in real time. The liquid level sensor can detect the liquid level of the cleaning liquid in the water tank and feed it back to the liquid replenishment system. The liquid replenishment system can receive the signal of the liquid level sensor and automatically replenish the cleaning liquid in the water tank. Fig.10As shown, the structure of the cleaning liquid management module 11 includes: a liquid storage unit 111, a concentration and liquid level detection unit 112, a control unit 113 and an execution unit 114 connected in sequence, wherein the liquid storage unit 111 is used to store cleaning liquid; the concentration and liquid level detection unit 112 is used to detect the concentration and liquid level of the cleaning liquid in the liquid storage unit 111, and transmit the detected concentration data and liquid level data to the control unit 113; the control unit 113 is used to generate a corresponding control signal according to the concentration data and liquid level data, and send the control signal to the execution unit 114; the execution unit 114 is used to execute the actions of discharging the cleaning liquid of the liquid storage unit 111, replenishing the chemical agent of the liquid storage unit 111, replenishing the water of the liquid storage unit 111, replacing the cleaning liquid of the liquid storage unit 111, recovering the cleaning liquid of the reaction chamber, and supplying liquid to the reaction chamber according to the control signal. By combining with the reaction chamber control device, automatic management of the cleaning liquid is realized, and the cleaning process is continuously carried out without the management of the cleaning liquid by a technician. The concentration liquid level detection unit 112 includes a liquid level sensor and a chemical analyzer for detecting concentration data. The detection tube on the chemical analyzer extends into the liquid storage unit 111. The liquid level sensor is arranged on the side wall of the liquid storage unit 111. The liquid level sensor and the chemical analyzer are connected to the control unit 113. The execution unit 114 includes: a cleaning liquid tube, a liquid replenishment tube, a water replenishment tube, a waste liquid tube, a liquid supply tube, a liquid exchange tube and a recovery tube. The outlet of the liquid replenishment tube, the outlet of the water replenishment tube, the outlet of the liquid exchange tube, and the outlet of the recovery tube all extend into the liquid storage unit 111. The cleaning liquid tube is arranged at the bottom end of the liquid storage unit 111. An infusion pump is provided on the cleaning liquid. The cleaning liquid tube is connected to the inlet of the liquid supply tube and the inlet of the waste liquid tube respectively through a three-way tube. The inlet of the waste liquid pipe is provided with a pneumatic valve, the inlet of the liquid supply pipe is provided with a pneumatic valve, the outlet of the liquid supply pipe is provided with a pneumatic valve, the outlet of the liquid infusion pipe is provided with a pneumatic valve, the outlet of the water replenishment pipe is provided with a pneumatic valve, the outlet of the liquid exchange pipe is provided with a pneumatic valve, and the outlet of the recovery pipe is provided with a pneumatic valve. All pneumatic valves on the liquid infusion pipe, water replenishment pipe, waste liquid pipe, liquid supply pipe, liquid exchange pipe and recovery pipe are connected to the control unit 113, and the infusion pump is connected to the control unit 113. A filter is provided on the liquid supply pipe. The device also includes a temperature detection unit 115, which is connected to the control unit 113 and is used to detect the temperature data of the cleaning liquid in the liquid storage unit 111 and send the temperature data to the control unit 113; the control unit 113 is also used to generate a corresponding control signal according to the temperature data and send the control signal to the execution unit 114; the execution unit 114 is also used to execute the action of automatically circulating and heating the cleaning liquid of the liquid storage unit 111 according to the control signal.The temperature detection unit (5) includes a temperature detector, the detection tube of the temperature detector extends into the liquid storage unit 111, and the temperature detector is connected to the control unit. The execution unit also includes: an automatic circulation pipe, the automatic circulation pipe is provided with a pneumatic valve, the inlet of the automatic circulation pipe is connected between the pneumatic valve at the outlet of the liquid supply pipe and the filter, and a cleaning liquid heating device is also provided between the pneumatic valve at the inlet of the automatic circulation pipe and the filter.

[0098] In the embodiment of the present invention, the control module 12 is composed of a PLC or an embedded controller, which can automatically adjust the operation of the power oscillation module 1, the sound wave acquisition module 5, the water pressure acquisition module 8, the cleaning liquid management module 11 and the clamping bracket 6 according to the sound wave, pressure and liquid level data collected. Through real-time feedback, the control module 12 control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, and ensures the efficiency and stability of the cleaning process. The control module 12 is composed of a PLC or an embedded controller, which can automatically adjust the operation of the ultrasonic transmission module, the signal acquisition module, the cleaning liquid management module and the clamping bracket according to the sound wave, pressure and liquid level data collected by the sensor. Through real-time feedback, the control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, and ensures the efficiency and stability of the cleaning process.

[0099] In the embodiment of the present invention, impedance matching refers to a working state in which the load impedance and the internal impedance of the excitation source are adapted to each other to obtain a maximum power output. The load impedance is equal to the internal impedance of the signal source, that is, their modulus and radiation angle are equal, and then distortion-free voltage transmission can be obtained on the load impedance. The load impedance is equal to the conjugate value of the internal impedance of the signal source, that is, their modulus is equal and the sum of the radiation angles is zero. At this time, the maximum power can be obtained on the load impedance. This matching condition is called conjugate matching. If the internal impedance of the signal source and the load impedance are both purely resistive, the two matching conditions are equivalent.

[0100] The main function of the impedance matching module 3 is to ensure that the signal will not be reflected during the transmission process, thereby improving energy efficiency and signal quality. By matching the characteristic impedance of the transmission line with the load impedance, the impedance matching module can reduce the energy loss of the signal during the transmission process and ensure that the signal can be transmitted efficiently. The transducer module 4 refers to a device that converts electrical energy into other forms of energy, such as converting electrical energy into mechanical energy, thermal energy, etc. In electronic systems, transducer modules usually involve the processing of high-frequency signals, so impedance matching becomes particularly important. Through impedance matching, it can be ensured that the signal will not be reflected during the transmission process due to impedance mismatch, thereby affecting the stability and efficiency of the signal. When connecting the impedance matching module 3 and the transducer module 4, the following points need to be noted:

[0101] Calculation and measurement: First, you need to calculate the effective frequency and trace length of the signal to determine whether impedance matching is required. If the effective wavelength of the signal is greater than 6 times the length of the signal trace, impedance matching needs to be considered.

[0102] Design and implementation: Impedance matching can be achieved by adjusting the characteristic impedance of the transmission line or using impedance matching circuits such as LC circuits. Specific methods include adjusting the physical length of the transmission line or connecting components such as capacitors and inductors in series.

[0103] Testing and verification: In practical applications, testing is needed to verify the effect of impedance matching to ensure that there is no obvious reflection and energy loss during signal transmission.

[0104] Through the above steps, the impedance matching module can be effectively connected to the transducer module to ensure efficient and stable operation of the system.

[0105] In the embodiment of the present invention, in order to enhance the control function of the cleaning liquid in the water tank 7, a refilling system is installed in the water tank 7. The refilling system can receive the signal of the liquid level sensor and replenish the cleaning liquid in the water tank. The signal acquisition module installed in the water tank 7 includes but is not limited to the sound wave acquisition module 5 and the water pressure acquisition module 8. Furthermore, a liquid level sensor, a thermometer, and a crystal surface high-definition camera or a scanning electron microscope can also be installed in the water tank 7. The liquid level sensor can detect the real-time detection liquid level of the cleaning liquid in the water tank 7 and feed it back to the refilling system.

[0106] In the embodiment of the present invention, the data processing and analysis module 10 and the cleaning liquid management module 11 adopt a digital power control loop of a DSPIC series single chip microcomputer combined with a multiplier.

[0107] The following effects are produced in the application of the embodiments of the present invention:

[0108] 1) Ensure the stability and uniformity of cavitation cleaning: The scattering and reflection of the ultrasonic waves generated by the transducer module 4 by the wall of the water tank 7 affects the actual cavitation cleaning negative pressure, causing the cavitation negative pressure in the water to be unstable. The cavitation negative pressure in the cleaning process in the water tank 7 is monitored in real time by the sound wave acquisition module 5, and the pressure data is accurately collected and fed back to reduce the interference of the wall of the water tank 7 on the cavitation effect.

[0109] 2) Adaptive control improves cleaning efficiency; the system can dynamically adjust cleaning parameters according to real-time data from the sound wave acquisition module 5, the water pressure acquisition module 8, the data processing and analysis module 10 and the cleaning liquid management module 11, and adopts composite ultrasonic technology to ensure the flexibility and efficiency of the cleaning process. By automatically adjusting the sound wave emission frequency, intensity and power, the cleaning efficiency is significantly improved.

[0110] In this embodiment, the wafer non-destructive composite ultrasonic cleaning system and its operation and control method include the following steps:

[0001] 1) Pre-cleaning: Before ultrasonic cleaning, a preliminary pre-cleaning is performed to remove most of the particles and loose contaminants on the surface of the wafer 9.

[0002] 2) Ultrasonic cleaning: Place the wafer 9 in a water tank 7 filled with cleaning liquid, turn on the power oscillation module 1, and the ultrasonic vibration generated by the transducer module 4 generates tiny bubbles that continuously form and burst in the cleaning liquid, forming cavitation shock waves and microjets to deeply clean the surface of the wafer 9.

[0003] 3) Rinsing: After cleaning, the wafer 9 is taken out and rinsed in pure water to remove residual cleaning solution and tiny particles.

[0004] 4) Drying: Finally, the rinsed wafer 9 is dried to ensure that no water stains remain on its surface.

[0005] In this embodiment, the cleaning and control method of the wafer non-destructive composite ultrasonic cleaning system includes:

[0006] (a) A cleaning method comprising the following steps:

[0007] (1) Pour cleaning liquid into the water tank, use the clamping bracket to clamp the wafer, and monitor the cleaning liquid level in real time through the cleaning liquid management module. The module detects the liquid level of the cleaning liquid through the liquid level sensor. When the liquid level is lower than the set value, the control system automatically triggers the liquid replenishment system to keep the cleaning liquid at an appropriate level;

[0008] (2) Immerse the wafer in the cleaning liquid and adjust the part of the wafer to be cleaned to the side where the transducer emits sound waves. Through the automatic positioning of the clamping bracket, the position sensor detects the size and position of the wafer, and the control system automatically adjusts the height and angle of the clamping bracket based on the feedback, so that the wafer surface is always located in the optimal cleaning area;

[0009] (3) The sound wave generating device emits an electrical signal of a preset voltage, which is received by the transducer device and converted into a sound signal of a specific frequency after being amplified and impedance matched by the signal amplifying device. The sound wave generating device emits an electrical signal of a preset voltage according to the command of the control system. The signal is amplified by the signal amplifying device, and after the signal transmission is optimized by the impedance matching device, it is transmitted to the transducer device for sound signal conversion. The control system monitors the feedback signals from the sound wave collecting device and the water pressure collecting device in real time, and automatically adjusts the voltage, transmission frequency and gain value to ensure that the ultrasonic wave maintains the best transmission conditions during the entire cleaning process;

[0010] (4) The transducer device emits an acoustic signal, and ultrasonic cavitation occurs in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the wafer surface. During the cleaning process, the water pressure collection device and the acoustic wave collection device monitor the acoustic pressure and acoustic signal in real time, and the control system automatically adjusts the intensity and frequency of the acoustic wave emission based on the feedback to ensure the stability and efficiency of the cleaning effect.

[0011] (b) The control method mainly controls the preset voltage and includes the following steps:

[0012] (1) Pour cleaning liquid into the water tank, use the clamping bracket to clamp the wafer, and place the water pressure acquisition device in the cleaning liquid. At this time, the control system will monitor the pressure environment of the cleaning liquid through the water pressure acquisition device and prepare to start the acoustic wave emission process;

[0013] (2) Adjust the position of the water pressure collection device. The control system automatically adjusts the probe position of the water pressure collection device through feedback signals to ensure that it is accurately positioned in the sound wave emission area of ​​the transducer device. This step is crucial to ensure that the water pressure collection device can effectively capture the sound pressure data generated during the sound wave emission process;

[0014] (3) Emitting original sinusoidal electrical signal pulses: The control system emits 3-5 cycles of sinusoidal electrical signal pulses through the sound wave generating device according to the preset voltage parameters. The electrical signal is amplified by the signal amplifying device and then adjusted by the impedance matching device to reduce reflection and loss and ensure transmission efficiency. Finally, the signal is received by the transducer and converted into a sound wave signal of the corresponding frequency;

[0015] (4) The transducer device emits a sound wave signal, causing ultrasonic cavitation in the cleaning liquid. At this time, the water pressure collection device begins to detect the negative pressure changes in the sound wave emission area. The water pressure collection device feeds back the measured negative pressure data to the control system in real time. Based on this feedback, the control system can automatically adjust the voltage, frequency and other emission parameters of the sound wave generating device to ensure the effectiveness of the cavitation phenomenon;

[0016] (5) Monitoring and processing of reflected sound wave signals: The sound wave acquisition device is placed on one side of the transducer device to capture the sound wave reflection signal. The sound wave acquisition device receives the reflection signal in real time and outputs the corresponding waveform data. The control system analyzes the waveform to determine whether the amplitude of the reflected waveform has reached the preset threshold. If the amplitude of the reflected waveform exceeds 1.5 times that when no cavitation occurs, the control system automatically determines that cavitation has occurred;

[0017] (6) Automatic determination of cavitation: The control system determines whether cavitation has occurred by comparing the amplitude of the reflected waveform with the preset amplitude threshold. If the amplitude of the reflected signal reaches or exceeds the set 1.5 times threshold, the system confirms that cavitation has occurred and automatically records the number of cavitation occurrences. If the threshold is not reached, the system determines that cavitation has not occurred and adjusts transmission parameters such as voltage or frequency.

[0018] (7) Calculation of cavitation probability: The system automatically calculates the cavitation probability based on the number of cavitation occurrences and the number of pulses emitted. This probability is used to determine the effectiveness of the cleaning process. The system can adjust in real time based on the frequency of cavitation to ensure that the cleaning effect reaches the best level.

[0019] (8) Voltage and frequency adjustment: According to the preset voltage interval, the system gradually increases or decreases the electrical signal voltage of the acoustic wave generator. After each voltage adjustment, the system will repeat steps (3) to (7) to automatically measure the cavitation probability under different negative pressure conditions.

[0020] (9) Generate cavitation probability curve and determine optimal cleaning parameters: The system generates a cavitation probability curve based on the cavitation probability data under different voltages and negative pressures. With negative pressure as the horizontal axis and cavitation probability as the vertical axis, the system automatically analyzes and obtains the negative pressure value when the cavitation probability reaches 50%, which is the cavitation threshold. The acoustic wave emission voltage corresponding to the negative pressure at this time will be set as the preset voltage of the cleaning system to ensure the best cleaning efficiency at this voltage.

[0021] The present invention is widely used in multiple links such as pre-diffusion cleaning, post-photolithography cleaning, and pre-oxidation cleaning in the semiconductor manufacturing process. It can significantly improve the cleanliness and flatness of the wafer surface, reduce the defect rate and increase the yield rate, and also help to improve the performance and reliability of semiconductor devices, providing strong support for the development of the semiconductor industry.

[0022] Based on the above embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention, so as to avoid exhaustively listing all implementation methods that are unnecessary and impossible to list comprehensively.

Claims

1. A wafer non-destructive composite ultrasonic cleaning system, comprising an ultrasonic generating module, a sound wave collecting module (5), a clamping bracket (6), a water tank (7), a water pressure collecting module (8), a data processing and analysis module (10), a cleaning liquid management module (11) and a control module (12); It is characterized in that The ultrasonic generating module comprises a power oscillation module (1), a signal amplification module (2), an impedance matching module (3) and a transducer module (4); the transducer module (4) is arranged on one side of a water tank (7), and a water pressure collection module (8) is arranged on the other side of the water tank (7); a clamping bracket (6) is arranged on the upper side of the water tank (7); the transducer module (4) is connected to a control module (12) in sequence through a sound wave collection module (5) and a data processing and analysis module (10); the control module (12) is connected to a control module (12) in sequence through a power oscillation module (1), a signal amplification module (2) and an impedance matching module (3); The matching module (3) is connected in series to the transducer module (4) to perform signal transmission and conversion; a cleaning liquid management module (11) is installed on the outer wall of the water tank (7); the lower end of the clamping bracket (6) extends into the water tank (7); the data processing and analysis module (10) uses the cavitation noise spectrum analysis method to timely adjust the working state of the transducer module (4) based on the ultrasonic cavitation effect and the working condition of the cleaning liquid in the water tank (7) collected in real time by the sound wave collection module (5) and the water pressure collection module (8), as well as the surface cleaning effect of the wafer (9) clamped by the lower end of the clamping bracket (6); the working process includes: 1) Inject cleaning liquid into a water tank (7) and use a clamping bracket (6) to clamp a wafer (9); 2) immersing the wafer (9) below the liquid level of the cleaning liquid, and adjusting the portion of the wafer (9) to be cleaned to the side where the transducer module (4) emits sound waves; 3) The power oscillation module (1) sends an electrical signal of a preset voltage to the signal amplification module (2) and the impedance matching module (3), and after amplification by the signal amplifier and impedance matching, the signal is received by the highly focused ultrasonic sensor of the transducer module (4) and converted into an acoustic signal of a specific frequency; 4) The transducer module (4) emits an acoustic signal and generates ultrasonic cavitation in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the surface of the wafer (9).

2. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The ultrasonic wave generating module is also equipped with a digital-to-analog converter DAC and a voltage-controlled oscillator VCO.

3. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The power oscillation module (1) comprises an input unit for setting the power and frequency working range of the power oscillation module (1), a control unit for adjusting the output frequency of the PWM signal according to the instruction input by the input unit, a power generation unit for amplifying and inverting the PWM signal input by the control unit, and a matching unit for receiving the electrical signal output by the power generation unit and converting the electrical signal into an ultrasonic wave. The input unit, the control unit, the power generation unit and the matching unit are electrically connected in sequence. In addition, a sampling unit is also included. The input end of the sampling unit is connected to the battery cell of the matching unit, and the output end of the sampling unit is electrically connected to the control unit. After the power oscillation module (1) is started, an instruction containing preset values ​​such as the output power, frequency, and start and stop information of the generator of the power oscillation module (1) is input through the input unit. Then, after receiving the start signal, the control unit first selects the middle frequency of the frequency range according to the instruction input by the input unit and transmits it to the power generation unit through the PWM signal. The power generation unit sends the signal to the matching unit through power amplification and inversion. The matching unit and the cleaning water tank form a resonant circuit to generate ultrasonic waves for cleaning. At the same time, the matching unit collects the matching information through the sampling unit. The current and voltage signals of the unit are collected, and the corresponding power value is obtained through the multiplier and fed back to the control unit; the control unit collects the feedback power value through the AD port and compares it with the power input by the input unit; if the two values ​​are not equal, the control unit adjusts the output PWM frequency; by adjusting the PWM frequency, comparing the input power and the actual power, the input power is gradually approached, and finally a constant power output is achieved; it should be pointed out that the maximum range of PWM frequency adjustment is the frequency range of the input unit input; the sampling unit includes a current transformer, a voltage transformer and a multiplier circuit, the current transformer collects the current signal of the matching unit and inputs it into the multiplier circuit, the voltage transformer collects the voltage signal of the matching unit and inputs it into the multiplier circuit, and the multiplier obtains the corresponding power value according to the current signal and the voltage signal and feeds it back to the control unit; the input unit includes a function button and a display, the function button is connected to the I / O port of the control unit, and the display communicates with the control unit through the SPI bus; the power generation unit includes a half-bridge inverter circuit composed of a MOS tube and a MOSFET; the matching unit includes a resonant circuit composed of an inductor and a transducer; the control unit is a single-chip microcomputer.

4. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The cleaning liquid management module (11) comprises a liquid level sensor and a liquid replenishment system, and is used to monitor and adjust the liquid level of the cleaning liquid in real time; the cleaning liquid management module (11) structure comprises: a liquid storage unit (111), a concentration liquid level detection unit (112), a control unit (113) and an execution unit (114) connected in sequence, the liquid storage unit (111) being used to store the cleaning liquid; the concentration liquid level detection unit (112) being used to detect the concentration and liquid level of the cleaning liquid in the liquid storage unit (111), and transmitting the detected concentration data and liquid level data to the execution unit (114); The control unit (113) is used to generate a corresponding control signal according to the concentration data and the liquid level data, and send the control signal to the execution unit (114); the execution unit (114) is used to execute the actions of discharging the cleaning liquid of the liquid storage unit (111), replenishing the chemical agent of the liquid storage unit (111), replenishing the water of the liquid storage unit (111), replacing the cleaning liquid of the liquid storage unit (111), recovering the cleaning liquid of the reaction chamber, and supplying liquid to the reaction chamber according to the control signal.

5. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The data processing and analysis module (10) is used to receive real-time data from the sound wave acquisition module (5) and the water pressure acquisition module (8), and to process and analyze the sound wave and pressure data using the built-in algorithm of the control module (12); the module feeds back the status of the cleaning process in real time, and automatically sends control instructions to the control module to adjust the voltage, frequency and other parameters of the sound wave emission device to ensure the cleaning effect; the data processing and analysis module (10) is used for signal acquisition and data analysis, and calculates the harmonic noise level of the corresponding harmonic generated by cavitation by analyzing the cavitation noise spectrum in a line spectrum extraction manner; The structure of the data processing and analysis module (10) includes a peak detection circuit, a low-peak coupling compensation circuit, and a feedback amplitude modulation circuit. The peak detection circuit detects the signal in the data transmission channel of the Internet of Things in real time. When the peak value is less than the 0.5V lower limit standard signal, the low-peak signal enters the low-peak coupling compensation circuit, performs a difference operation with the +5V upper limit standard signal, and is coupled to the peak detection circuit. When the peak value is higher than or equal to the +5V upper limit standard signal, a three-stage step-by-step conduction circuit composed of transistors Q1, Q2, and Q3 is conducted step by step, and the first to third stage transistors are conducted step by step to change the amplification factor of the proportional amplifier circuit with the operational amplifier AR3 as the core. After voltage stabilization, the voltage stabilization circuit outputs a 0.5V to +5V standard signal.

6. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The control module (12) is composed of a PLC or an embedded controller, and can automatically adjust the operation of the power oscillation module (1), the sound wave collection module (5), the water pressure collection module (8), the cleaning liquid management module (11) and the clamping bracket (6) according to the collected sound wave, pressure and liquid level data; through real-time feedback, the control module (12) control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, thereby ensuring the high efficiency and stability of the cleaning process; the control module (12) is composed of a PLC or an embedded controller, and can automatically adjust the operation of the power oscillation module (1), the sound wave collection module (5), the water pressure collection module (8), the cleaning liquid management module (11) and the clamping bracket (6) according to the collected sound wave, pressure and liquid level data; through real-time feedback, the control module (12) control system automatically adjusts the voltage, frequency and gain to adapt to different cleaning conditions and requirements, thereby ensuring the high efficiency and stability of the cleaning process.

7. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The sound wave collection module (5) is a multi-point collection device that collects and analyzes sound pressure and sound wave signals at multiple points simultaneously.

8. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The clamping bracket (6) is equipped with a position sensor and an electric actuator to automatically adjust the position of the clamping bracket to ensure that the wafer surface is in the optimal cleaning area.

9. The wafer non-destructive composite ultrasonic cleaning system and its operation and control method according to claim 1, It is characterized in that The signal amplification module (2) includes an automatic gain control function, and the amplification factor is adjusted by the control module; the structure of the signal amplification module (2) includes a signal amplifier and a power supply module, the power supply module is electrically connected to the signal amplifier, the power supply module includes a power adapter and a storage battery, the power adapter is electrically connected to two external power supplies at the same time, the storage battery is electrically connected to the power adapter, and the power adapter is provided with a storage circuit and a switching switch for switching the two external power supplies; the switching switch switches the two external power supplies, so that when one of the external power supplies fails to supply power, the other external power supply can continue to supply power to the signal amplifier, and when the two external power supplies fail to supply power at the same time, the storage circuit first supplies power to the signal amplifier, and then the storage battery continues to supply power to the signal amplifier, so as to ensure that the signal amplifier always maintains a normal use state without interruption time, so that the use of the signal amplification device is relatively reliable.

10. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The transducer module (4) has temperature compensation and automatic calibration functions, and can automatically adjust under different environmental conditions to ensure accurate conversion and emission of acoustic signals; the transducer module (4) receives electrical signals of different periods, converts them into acoustic signals of corresponding frequencies, and emits them; a highly focused ultrasonic sensor is arranged in the transducer module (4), and the highly focused ultrasonic sensor has an outer diameter of 64 mm and a focal length of 63.2 mm.

11. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The impedance matching module (3) comprises three variable capacitance diodes and at least one PI type circuit with a fixed inductance; the variable capacitance diodes perform impedance adjustment according to a bias voltage.

12. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The sound wave acquisition module (5) has an automatic pressure calibration function, and can automatically calibrate the pressure sensor according to the characteristics of the cleaning fluid; the sound wave acquisition module (5) has waveform analysis and intelligent filtering functions, and can automatically adjust under different environmental conditions to ensure accurate conversion and emission of sound signals; the sound wave acquisition module (5) has the function of collecting sound signals and outputting sound signal waveforms; the sound wave acquisition module (5) is a multi-point acquisition device, and can collect and analyze sound pressures and sound wave signals at multiple points at the same time.

13. The wafer non-destructive composite ultrasonic cleaning system according to claim 1, It is characterized in that The cleaning and control methods of the wafer non-destructive composite ultrasonic cleaning system include: (a) A cleaning method comprising the following steps: (1) Inject cleaning liquid into the water tank, use a clamping bracket to clamp the wafer, and monitor the cleaning liquid level in real time through the cleaning liquid management module; the module detects the cleaning liquid level through a liquid level sensor. When the liquid level is lower than the set value, the control system automatically triggers the liquid replenishment system to keep the cleaning liquid at an appropriate level; (2) Immerse the wafer in the cleaning liquid and adjust the portion of the wafer to be cleaned to the side where the transducer emits sound waves; through the automatic positioning of the clamping bracket, the position sensor detects the size and position of the wafer, and the control system automatically adjusts the height and angle of the clamping bracket based on the feedback, so that the wafer surface is always located in the optimal cleaning area; (3) The sound wave generating device emits an electrical signal of a preset voltage, which is amplified and impedance matched by the signal amplifying device, and then received by the transducer device and converted into a sound signal of a specific frequency; the sound wave generating device emits an electrical signal of a preset voltage according to the instruction of the control system, and the signal is amplified by the signal amplifying device, and after the signal transmission is optimized by the impedance matching device, it is transmitted to the transducer device for sound signal conversion; the control system monitors the feedback signals from the sound wave collecting device and the water pressure collecting device in real time, and automatically adjusts the voltage, transmission frequency and gain value to ensure that the ultrasonic wave maintains the best transmission conditions during the entire cleaning process; (4) The transducer device emits an acoustic signal and generates ultrasonic cavitation in the cleaning liquid, thereby achieving ultrasonic cavitation cleaning of the wafer surface; during the cleaning process, the water pressure collection device and the acoustic wave collection device monitor the acoustic pressure and acoustic signal in real time, and the control system automatically adjusts the intensity and frequency of the acoustic wave emission based on the feedback to ensure the stability and efficiency of the cleaning effect; (b) The control method mainly controls the preset voltage and includes the following steps: (1) Inject cleaning liquid into the water tank, use a clamping bracket to clamp the wafer, and place the water pressure acquisition device in the cleaning liquid; at this time, the control system will monitor the pressure environment of the cleaning liquid through the water pressure acquisition device and prepare to start the acoustic wave emission process; (2) Adjust the position of the water pressure collection device. The control system automatically adjusts the probe position of the water pressure collection device through feedback signals to ensure that it is accurately positioned in the sound wave emission area of ​​the transducer device. This step is crucial to ensure that the water pressure collection device can effectively capture the sound pressure data generated during the sound wave emission process. (3) Emitting original sinusoidal electrical signal pulses: The control system emits 3-5 cycles of sinusoidal electrical signal pulses through the sound wave generating device according to the preset voltage parameters; the electrical signal is amplified by the signal amplifying device, and then the signal is adjusted by the impedance matching device to reduce reflection and loss and ensure transmission efficiency; finally, the signal is received by the transducer device and converted into a sound wave signal of the corresponding frequency; (4) The transducer device emits a sound wave signal, causing ultrasonic cavitation to occur in the cleaning liquid; at this time, the water pressure collection device begins to detect the negative pressure change in the sound wave emission area; the water pressure collection device feeds back the measured negative pressure data to the control system in real time; based on this feedback, the control system automatically adjusts the voltage, frequency and other emission parameters of the sound wave generating device to ensure the effectiveness of the cavitation phenomenon; (5) Monitoring and processing of reflected sound wave signals: The sound wave acquisition device is placed on one side of the transducer device to capture the sound wave reflection signal; the sound wave acquisition device receives the reflection signal in real time and outputs the corresponding waveform data; the control system analyzes the waveform to determine whether the amplitude of the reflected waveform has reached a preset threshold; if the amplitude of the reflected waveform exceeds 1.5 times that of the state when cavitation has not occurred, the control system automatically determines that cavitation has occurred; (6) Automatic determination of cavitation: The control system determines whether cavitation has occurred by comparing the amplitude of the reflected waveform with a preset amplitude threshold. If the amplitude of the reflected signal reaches or exceeds 1.5 times the preset threshold, the system confirms that cavitation has occurred and automatically records the number of cavitation occurrences. If the threshold is not reached, the system determines that cavitation has not occurred and adjusts the voltage or frequency transmission parameters. (7) Calculation of cavitation probability: The system automatically calculates the cavitation probability based on the number of cavitation phenomena and the number of pulses emitted. This probability is used to determine the effectiveness of the cleaning process. The system can adjust in real time according to the frequency of cavitation phenomena to ensure that the cleaning effect reaches the best level. (8) Voltage and frequency adjustment: The system gradually increases or decreases the electrical signal voltage of the acoustic wave generator according to a preset voltage interval; after each voltage adjustment, the system will repeat steps (3) to (7) to automatically measure the cavitation probability under different negative pressure conditions; (9) Generate cavitation probability curve and determine optimal cleaning parameters: The system generates a cavitation probability curve based on the cavitation probability data under different voltages and negative pressures. With negative pressure as the horizontal axis and cavitation probability as the vertical axis, the system automatically analyzes and obtains the negative pressure value when the cavitation probability reaches 50%, i.e., the cavitation threshold. The acoustic wave emission voltage corresponding to the negative pressure at this time will be set as the preset voltage of the cleaning system to ensure the best cleaning efficiency at this voltage.

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